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2022 Faculty Awards

Dr. Kim Selected as 2022 Straumann New Periodontist Annual Meeting Scholarship Recipient

The college is pleased to announce that Jaewon Kim, D.D.S., M.S.D., Ph.D., received the 2022 Straumann New Periodontist Annual Meeting Scholarship at the American Academy of Periodontology annual meeting.

Straumann, an implant company, selects a few candidates each year for the scholarship. Those who are in consideration must have finished a periodontics residency program recently and are starting their career as a periodontist. Candidates also have to go through a rigorous process to be considered for the scholarship.

In addition, Dr. Kim was one of the finalists for the 2021 American Academy of Periodontology scholarship. “Together with the talented residents and faculties, I will pursue my career further in research, publications and in clinical skills so I can make OU Periodontics program recognized at AAP and advanced beyond any other programs in United States,” said Dr. Kim.

Dr. Kim was also awarded a similar scholarship from Nobel Biocare, an implant company, which only gives to residents during his periodontics residency in Buffalo, New York.

Dr. Wood Receives Champion of Health Award

Chalmers Rieger Wood III, D.D.S., founder of Oklahoma Mission of Mercy (OkMOM), won the Champion of the Uninsured award from the annual The Champions of Health Awards ceremony presented by Blue Cross and Blue Shield of Oklahoma in July 2022.

“I was quite surprised and humbled to receive this award,” said Dr. Wood. “I never dreamed that OkMOM would have such a lasting impact on our state. This award really goes to all the dentists, hygienists, dental students and hygiene students, as well as the ODA staff and community volunteers, who continue to serve Oklahomans.”

Dr. Wood started OkMOM in 2010 in Tulsa, Oklahoma. Since its inception, the free two-day clinic has treated more than 17,000 patients and donated more than $14 million in dental care.

The Champions of Health awards are presented yearly and honor those who are making a difference in health care.

Characterization of Experimental Nanoparticulated Dental Adhesive Resins with LongTerm Antibacterial Properties

For the first time in dentistry, experimental adhesive resins containing nanoparticles can be antibacterial two years after polymer synthesis. The University of Oklahoma College of Dentistry's own Sharukh S. Khajotia, B.D.S., M.S., Ph.D., associate dean for research and innovation, and Fernando Luis Esteban Florez, D.D.S., M.S., Ph.D., associate professor and division head of dental biomaterials, participated in this collaborative research. The following article was published by Nanomaterials, a scientific journal.

Dental caries continues to pose a major health burden in numerous countries. This biofilm-originated disease [1] is estimated to affect 3.5 billion people [2] and to represent around 4.6% of the total global expenditures in health care [3]. Clinical manifestations include the progressive and irreversible dissolution [4,5] of dental hard tissues (e.g., enamel, dentin and cementum), cavitation, pain and tooth loss. The treatment of dental caries revolves around the mechanical removal of disorganized and infected tissues using hand-held instruments (e.g., either static or rotary) and the placement of a dental biomaterial (e.g., metal, polymer or ceramic) to restore the esthetics and masticatory function of affected tissues.

Over the years, composite resins became the first choice of restorative materials among patients and clinicians due to its mercury-free compositions [6] and superior properties (e.g., handling and esthetic) [7,8,9]. In fact, composite resin restorations are the most prevalent biomedical intervention in human beings, with more than 800 million placed every year [10]. Despite such widespread acceptance and utilization, previous studies indicated that these materials are associated with limited-service lives (between 5–7 years), [11] experience polymerization shrinkage and accumulate more biofilms, when compared to other restorative materials [9,12,13]. When combined, these factors may shift the ecology of the oral cavity from a healthy state into a disease-associated state [14].

Streptococcus mutans, a Gram-positive and facultatively anaerobic bacteria, has been widely accepted as a major contributor to the development of dental caries (primary and secondary) due to their (i) ability to adhere and accumulate onto the surfaces of teeth through a disaccharide-dependent mechanism, (ii) ability to deposit an extracellular matrix that protects cells from external aggressors, (iii) ability to metabolize a wide variety of complex carbohydrates into organic acids, and (iv) the ability to thrive in acidic environments [15]. Even though S. mutans is not solely responsible for the occurrence of dental caries, these undisputable features have made S. mutans an important model organism in oral antibacterial research [16].

Secondary caries develop between dental adhesive resins and the tooth structure, and are considered the primary reason for the failure of polymer-based bonded restorations [17]. According to previous studies, current dental adhesive resins are formulated using a combination of hydrophilic and hydrophobic components [18] that phase-separate when applied onto water-rich tissues [19]. This chemical instability leads to incomplete envelopment of exposed collagen fibrils and the establishment of porous hybrid layers that are prone to failure by biodegradation, hydrolysis, esterases and biofilms [20]. This significant problem has precipitated the execution of several studies to improve the physical, chemical and biological properties of current polymer formulations. Ideally, dental adhesive resins should be able to establish interfaces that are hermetically sealed, are dimensionally stable, prevent the formation of cariogenic biofilms, and precipitate highly organized crystalline structures to fill the gaps from the incomplete envelopment of collagen fibrils and polymerization shrinkage [21,22,23].

Despite significant investments by the manufacturing and scientific communities, newly developed materials containing antibacterial agents, quaternary ammonium compounds, [13] or metaloxide nanoparticles (e.g., zinc and titanium) [24,25] failed to sustain long-term antibacterial properties and did not extend the service lives of composite restorations, thereby underscoring the need for the development of novel materials with long-term biological properties. Pérez-Mondragón et al., [26] while investigating the shelf-life stability in terms of the degree of conversion, ultimate tensile strength and color of dental adhesive resins (commercially available and experimental) at different periods of simulated shelf-life (37 °C; 6, 18, and 24 months), have demonstrated that experimental materials displayed higher shelf-life stability (in terms of the degree of conversion), when compared to commercially available materials. However, experimental materials displayed mechanical and optical properties that were similar (p > 0.05) to those of the control group, independently of the time-point considered [26].

Recent advances in the field of material sciences and nanotechnology enabled the synthesis and incorporation of metaloxide nanoparticles (e.g., zinc oxide, silver and titanium) into dental polymers (denture base, dental adhesives and composite resins). These nanoparticulated systems have become prevalent in many areas of dental research, including orthodontics, dental materials, bleaching, implants and prosthodontics [27], because of their intrinsic optical, physical, biological and chemical properties [28,29]. Recent studies investigated the utility of silver, zinc, copper, titanium, calcium fluoride and magnesium nanoparticles [30,31] in the prevention of secondary caries because they have been shown to disrupt bacterial metabolism and biofilm formation [32].

Titanium dioxide (TiO2, anatase, rutile or brookite) is known for its relevant physical, chemical, antimicrobial and biocompatibility properties [33]. Nanoparticles of TiO2 (TiO2-np) are typically white, have diameters around 25 nm, have high refractive index, are corrosion resistant, display high microhardness values [20,34], and were demonstrated to be effective against numerous microorganisms, including Candida albicans, Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, and Lactobacillus acidophilus [35]. However, despite these relevant characteristics, TiO2-np have large bandgaps (3.2204 eV, for anatase) and require the utilization of UV irradiation to generate different types of reactive oxygen species (ROS) [34]. Even though the photocatalysis of TiO2-np is feasible from the electronic standpoint, the UV dose of energy required to promote surface disinfection has been demonstrated to be harmful to eukaryotic cells and tissues, [36] which significantly restricts its widespread utilization in dental applications.

Doping the crystal lattice of TiO2-np with metals and non-metals has been previously shown to decrease the bandgap of Titania (2.47 eV) [37] and allow the utilization of visible light irradiation, which is widely used in dentistry, for the generation of ROS. The synthesis, incorporation and covalent functionalization of visible light-responsive nitrogen-doped titanium dioxide nanoparticles (N_TiO2) into a commercially available dental adhesive resin (OptiBond Solo Plus, Kerr Corp., USA; OPTB) has been recently reported by Esteban Florez et al. [34,38,39]

Experimental adhesive resins displayed strong antibacterial and biomimetic properties when irradiated with visible light [34] and were less soluble and more biocompatible [20], when compared to commercially available materials, which suggests that nanoparticulated materials may hold the promise to decrease the incidence of secondary caries and to extend the service lives of polymer-based adhesive restorations.

Therefore, the objective of the present study was to characterize the (i) degree of conversion at the time of polymer synthesis and after two years of simulated shelflife, (ii) biaxial flexure strength, (iii) flexural modulus, (iv) surface roughness, (v) elastic modulus, and (vi) long-term antibacterial properties of experimental dental adhesive resins, containing varying concentrations of N_TiO2 (10%, 20%, and 30%, v/v%).

Kury Takes First Place in Paffenger Award

The college is pleased to announce that former Fulbright Scholar Matheus Kury, D.D.S., M.S., was awarded the first place Paffenbarger Award category at the Academy of Dental Materials 2022 annual meeting. The meeting was held in Athens, Greece, from Sept. 27-Oct. 1, 2022.

The Paffenbarger Award was created in the 1980s to recognize the best paper in the field of dental materials. Since then, this award has been presented annually.

Dr. Kury’s research, “Development of In-Office Bleaching Gels Containing Co-Doped Titanium Dioxide Nanoparticles,” was supervised by advisor, Vanesa Cavalli Gobbo of Brazil, Fernando Luis Esteban Florez, D.D.S., M.S., Ph.D., division head of dental biomaterials at the college, and Sharukh Khajotia, B.D.S., M.S., Ph.D., associate dean for research and innovation at the college.

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